JPWO2017081846A1 - Power system - Google Patents

Abstract

  In the power supply system (1), a plurality of power storage modules (11) to (14) are connected in series in order to increase the safety against flooding while suppressing the cost in the power supply system. The fuse (F1) is inserted at a position where the plurality of power storage modules (11)-(14) are divided into the first group and the second group in a path connecting the plurality of power storage modules (11)-(14) in series. Is done. The positive electrode side contactor (RY1) is inserted at a position where the plurality of power storage modules belonging to the first group are divided into the first sub group and the second sub group. The negative contactor (RY2) is inserted at a position where the plurality of power storage modules belonging to the second group are divided into the first subgroup and the second subgroup.

Description

  The present invention relates to a power supply system including a plurality of power storage modules connected in series.

  In recent years, hybrid vehicles (HV), plug-in hybrid vehicles (PHV), and electric vehicles (EV) have become widespread. These vehicles are equipped with a power supply system in which power storage modules for supplying driving power to a traveling motor are connected in multiple stages. In the case of a traveling motor that requires a high voltage, the power supply system can be increased in voltage by increasing the number of power storage modules in series.

  When a power supply system installed in a vehicle is submerged due to submersion of the vehicle or leakage of coolant liquid for cooling, there is a possibility that a nearby storage battery cell may directly short-circuit or a storage battery cell may be short-circuited via a metal casing. is there. When the cell is short-circuited due to a high potential difference, arc discharge occurs, and the arc can open a hole in the battery can, and there is a risk that electrolyte etc. leaks and leads to ignition.

JP 2009-238644 A

  To increase the breakdown voltage of the cell, it is effective to lengthen the insulation distance or use high-spec parts, but this leads to an increase in the size and cost of the power supply system.

  This invention is made | formed in view of such a condition, The objective is to provide the technique which raises the safety | security with respect to flooding, suppressing cost in a power supply system.

  In order to solve the above problems, a power supply system according to an aspect of the present invention includes a plurality of power storage modules connected in series and a plurality of power storage modules connected to each other on a path connecting the plurality of power storage modules in series. A fuse inserted at a position to be divided into a group and a second group; a positive contactor inserted at a position at which a plurality of power storage modules belonging to the first group are divided into a first subgroup and a second subgroup; And a negative electrode side contactor inserted at a position where a plurality of power storage modules belonging to the second group are divided into a first sub group and a second sub group.

  It should be noted that any combination of the above-described constituent elements and a representation of the present invention converted between a method, an apparatus, a system, and the like are also effective as an aspect of the present invention.

  ADVANTAGE OF THE INVENTION According to this invention, the safety | security with respect to flooding can be improved, suppressing cost in a power supply system.

It is a figure which shows the general circuit structural example of the vehicle-mounted power supply system. It is a figure which shows the circuit structural example of the vehicle-mounted power supply system which concerns on embodiment of this invention. It is the schematic diagram which looked at the arrangement | positioning in the housing | casing of each component of the power supply system of FIG. It is the schematic diagram which looked at the A-A 'cross section of FIG. 3 from the right side. It is the schematic diagram which looked at the B-B 'cross section of FIG. 3 from the lower side.

  FIG. 1 is a diagram illustrating a general circuit configuration example of an in-vehicle power supply system 1. The power supply system 1 is a power storage system that stores electric power to be supplied to the motor 3. The power supply system 1 is provided in the vehicle separately from a 12V secondary battery (usually a lead battery is used) for auxiliary equipment.

  During power running, the inverter 2 converts the DC power supplied from the power supply system 1 into AC power and supplies it to the motor 3. During regeneration, AC power supplied from the motor 3 is converted to DC power and supplied to the power supply system 1. For example, a three-phase AC synchronous motor is used as the motor 3. Hereinafter, in this specification, a high-voltage motor of 300 V or higher is assumed. In the power running mode, the motor 3 rotates based on the electric power supplied from the inverter 2 to drive the vehicle. In the regeneration mode, power is generated by the rotation based on the deceleration energy of the vehicle, and the power supply system 1 is charged via the inverter 2.

  The power supply system 1 includes a plurality of power storage modules 11-14, a control circuit 20, a connector 30, a positive contactor RY1, a negative contactor RY2, a precharge resistor R1, a precharge contactor RY3, a current sensor CT1, and a fuse F1 connected in series. These are housed in a housing.

  Each power storage module 11-14 includes a plurality of single cells connected in series. A single cell is configured by connecting one or a plurality of single cells in parallel. As the single cell, a lithium ion cell, a nickel hydrogen cell, an electric double layer capacitor cell, or the like can be used. Hereinafter, in this specification, an example in which a lithium ion cell (nominal voltage: 3.6-3.7 V) is used is assumed, and an example in which the number of series is designed around 20 is assumed. Furthermore, an example in which four power storage modules having such a configuration are connected in series is assumed.

  The connector 30 is a current input / output terminal of the power supply system 1 and uses a high voltage specification connector. The connector 30 includes a male or female terminal that fits with a connector at the tip of a wire harness connected to the inverter 2.

  The positive electrode side contactor RY1 is inserted between the positive wiring connected to the connector 30 and the positive wiring connected to the positive terminals (a positive terminal of the first power storage module 11 in FIG. 1) of the plurality of power storage modules 11-14. The negative contactor RY2 is inserted between the negative wiring connected to the connector 30 and the negative wiring connected to the negative terminals of the plurality of power storage modules 11-14 (the negative terminals of the fourth power storage module 14 in FIG. 1).

  A precharge circuit is connected in parallel with the positive electrode side contactor RY1. The precharge circuit has a precharge resistor R1 and a precharge contactor RY3 connected in series. Large relays can be used for the positive contactor RY1, the negative contactor RY2, and the precharge contactor RY3.

  The precharge contactor RY3 is closed before the positive electrode side contactor RY1 is closed together with the negative electrode side contactor RY2, and charges a precharge capacitor (not shown) connected in parallel with the motor 3. Thereafter, the positive electrode side contactor RY1 is closed, and power supply to the motor 3 is started. The inrush current to the motor 3 can be suppressed by this control procedure.

  A current sensor CT1 and a fuse F1 are inserted on a current path connecting the four power storage modules 11-14 in series. The current sensor CT1 detects the value of the current flowing through the current path and outputs it to the control circuit 20. As the current sensor CT1, a clamp-type current sensor, a current sensor using a shunt resistor, a current sensor using a Hall element, or the like can be used. The fuse F1 is blown when a large current of a specified value or more flows to interrupt the current path.

  The control circuit (also referred to as a battery ECU) 20 manages and controls the plurality of power storage modules 11-14. The control circuit 20 acquires the value of the current flowing through the plurality of power storage modules 11-14 connected in series from the current sensor CT1. The control circuit 20 acquires a voltage value and a temperature value detected by a voltage sensor (not shown) and a temperature sensor (not shown) in each power storage module 11-14.

  Based on the acquired current value, voltage value, and temperature value, the control circuit 20 determines that an abnormality (eg, overvoltage, overcurrent) has occurred in at least one of the plurality of power storage modules 11-14. Open RY1 and negative electrode side contactor RY2 (turn off).

  FIG. 2 is a diagram illustrating a circuit configuration example of the in-vehicle power supply system 1 according to the embodiment of the present invention. In the following, description will be made centering on differences from the general circuit configuration shown in FIG. The current sensor CT1 and the fuse F1 are inserted in a position where the plurality of power storage modules 11-14 are divided into two groups of a first group and a second group on the current path connecting the plurality of power storage modules 11-14 in series. Is done. In FIGS. 1 and 2, the first power storage module 11 and the second power storage module 12 are included in the first group, and the third power storage module 13 and the fourth power storage module 14 are included in the second group. That is, the current sensor CT <b> 1 and the fuse F <b> 1 are inserted between the second power storage module 12 and the third power storage module 13.

  In the circuit configuration according to the embodiment shown in FIG. 2, the positive electrode side contactor RY1 is inserted at a position where the plurality of power storage modules belonging to the first group are divided into two. In the present embodiment, positive electrode side contactor RY1 is inserted between first power storage module 11 and second power storage module 12. The negative contactor RY2 is inserted at a position where the plurality of power storage modules belonging to the second group are divided into two. In the present embodiment, the negative electrode side contactor RY2 is inserted between the third power storage module 13 and the fourth power storage module 14.

  Thus, the positive electrode side contactor RY1, the fuse F1, and the negative electrode side contactor RY2 are respectively inserted at positions where the plurality of power storage modules 11-14 are divided into four. The current sensor CT1 is not limited to being between the second power storage module 12 and the third power storage module 13 as long as it is inside the positive contactor RY1 and the negative contactor RY2, and may be inserted at another position.

  FIG. 3 is a schematic view of the arrangement in the housing of each component of the power supply system 1 of FIG. 2 as viewed from above. The inside of the housing is divided into five areas, and each area is partitioned by a partition formed of an insulating material. The dotted line in FIG. 3 shows the partition.

  In FIG. 3, the first power storage module 11 is disposed in the upper right area 1, the second power storage module 12 is disposed in the upper left area 2, the third power storage module 13 is disposed in the lower left area 3, and the lower right area 4. The fourth power storage module 14 is disposed at the bottom. The housing of each power storage module 11-14 is installed in a state of being electrically insulated from the surroundings. Since robustness is required for in-vehicle use, a metal housing is often used for the housing of the power storage module. The metal housing that houses each power storage module 11-14 is installed in a state of being insulated from the housings of other power storage modules and the entire power supply system 1.

  In the central area 5, the connector 30, the control circuit 20, the positive contactor RY1, the negative contactor RY2, the precharge contactor RY3, the precharge resistor R1, the current sensor CT1, and the fuse F1 are arranged.

  FIG. 4 is a schematic view of the A-A ′ cross section of FIG. 3 viewed from the right side. FIG. 5 is a schematic view of the B-B ′ cross section of FIG. 3 viewed from below. As shown in FIGS. 4 and 5, the connector 30 is disposed at the bottom of the housing. The 1st electrical storage module 11, the 2nd electrical storage module 12, the 3rd electrical storage module 13, and the 4th electrical storage module 14 are arrange | positioned on the 1 step | paragraph. The control circuit 20 is arranged on the first stage. A positive electrode side contactor RY1, a negative electrode side contactor RY2, a precharge contactor RY3, a precharge resistor R1, a current sensor CT1, and a fuse F1 are arranged at the top.

  As shown in FIG. 4, the area 1-4 has a predetermined length (for example, several centimeters) and a bottom. The area 5 is raised to the same height as the top surface of the first power storage module 11 to the fourth power storage module 14 and is the bottom. The raised bottom portion also serves as an insulating wall between the first power storage module 11 and the second power storage module 12 and the third power storage module 13 and the fourth power storage module 14.

  A positive electrode terminal and a negative electrode terminal extend from the upper surfaces of the first power storage module 11 to the fourth power storage module 14, and each positive electrode terminal and each negative electrode terminal are connected according to the connection relationship shown in the circuit diagram shown in FIG. 2. Connected to the previous terminal with a bus bar. In addition, the positive electrode terminal of the 1st electrical storage module 11 is connected to the positive electrode terminal of the connector 30 with a wire harness, and the negative electrode terminal of the 4th electrical storage module 14 is connected to the negative electrode terminal of the connector 30 with a wire harness. As shown in FIG. 5, the raised bottom portion of the area 5 has a portion that is lowered by one step, and the control circuit 20 is disposed in that portion.

  The behavior when the power supply system 1 is submerged in the above arrangement example will be described. First, when the connector 30 is submerged and the positive electrode terminal and the negative electrode terminal of the connector 30 are short-circuited, a large current flows between the first power storage module 11 and the fourth power storage module 14, and the fuse F1 is melted. At this stage, the first power storage module 11 and the second power storage module 12, and the third power storage module 13 and the fourth power storage module 14 are electrically separated.

  Next, when the water level rises and a part of the control circuit 20 is submerged, the control circuit 20 opens the positive electrode side contactor RY1 and the negative electrode side contactor RY2 due to the detection of the circuit abnormality (turn off). At this stage, the first power storage module 11 and the second power storage module 12 are electrically separated, and the third power storage module 13 and the fourth power storage module 14 are electrically separated. That is, the first power storage module 11 to the fourth power storage module 14 are all electrically separated. At this stage, the upper portions of the first power storage module 11 to the fourth power storage module 14 are not submerged, and the positive terminal and the negative terminal of the first power storage module 11 to the fourth power storage module 14 are not submerged. Further, the high voltage circuit portion of the control circuit 20 is not submerged.

  Further, the water level rises, the entire first power storage module 11 to fourth power storage module 14 are submerged, and the cells in each power storage module are short-circuited.

  As described above, according to the present embodiment, by providing a height difference in the arrangement of the connector 30, the first power storage module 11 to the fourth power storage module 14, the fuse F1, the positive contactor RY1, and the negative contactor RY2, It is possible to control the order of occurrence of short circuits due to water immersion. That is, by disposing the connector 30 at a position lower than the fuse F1, it is possible to ensure that the fuse F1 is normally melted when the connector 30 is submerged. Further, by disposing the control circuit 20 at a position lower than the positive electrode side contactor RY1 and the negative electrode side contactor RY2, it is ensured that the positive electrode side contactor RY1 and the negative electrode side contactor RY2 operate normally when the control circuit 20 is submerged. Can do.

  Further, by disposing the control circuit 20 at a position higher than the connector 30, control is performed so that the interruption of the current path by the positive contactor RY1 and the negative contactor RY2 occurs after the interruption of the current path by the fuse F1. be able to. When both the cut-off timings are the same, the transient current increases. However, in this embodiment, a time difference occurs between the cut-off timings of both, and thus the transient current can be suppressed small.

  In the normal installation state, the connector 30 is submerged first. However, when the submersion into the power supply system 1 is stopped only when the connector 30 is submerged (when the rise in water level is stopped), the control circuit 20 is not submerged. It will be. In this case, if the fuse F1 and the connector 30 are replaced with new ones, it is not necessary to replace the control circuit 20, so that the repair cost can be reduced. In addition, the work of replacing the wiring that occurs when the control circuit 20 is replaced does not occur.

  Further, the positive electrode side contactor RY1, the fuse F1, and the negative electrode side contactor RY2 are arranged so as to divide the plurality of power storage modules connected in series into four equal parts. Thereby, the voltage applied between the cells when the cells are short-circuited can be reduced. The positive side contactor RY1, the fuse F1, and the negative side contactor RY2 are elements generally used in the power supply system 1, and are not newly added elements. Therefore, an increase in cost and an increase in circuit scale due to the addition of a new element do not occur. By changing the arrangement of the positive side contactor RY1, the fuse F1, and the negative side contactor RY2, the maximum voltage applied to the cell when the cell is short-circuited due to water immersion can be reduced to approximately ¼. Therefore, it is possible to keep the specifications of the pressure-resistant structure of the cell at a low cost while ensuring safety.

  In addition, by disposing the power storage module covered with the metal casing in a state of being electrically insulated from other power storage modules and the system casing, the voltage applied between the cells that are short-circuited through the metal casing is reduced. be able to. In addition, the voltage applied between the cells that are short-circuited through the metal housing can be increased by sandwiching an insulating material between the battery can containing the cell and the metal housing, or by increasing the distance between the battery can and the metal housing. Can be reduced. By taking these measures, safety against flooding can be further enhanced.

  The present invention has been described based on the embodiments. These embodiments are exemplifications, and it will be understood by those skilled in the art that various modifications can be made to combinations of the respective constituent elements and processing processes, and such modifications are within the scope of the present invention. is there.

  In the above-described embodiment, an example in which a plurality of power storage modules connected in series is four has been described. However, the present invention can also be applied to a case of five or more. For example, when the plurality of power storage modules is eight, the positive electrode side contactor RY1, the fuse F1, and the negative electrode side contactor RY2 are respectively arranged at the positions divided into two. When there are six power storage modules, the positive electrode side contactor RY1, the fuse F1, and the negative electrode side contactor RY2 are respectively arranged at positions where the battery module is divided into two, one, two, and one. Further, when the plurality of power storage modules is seven, the positive contactor RY1, the fuse F1, and the negative contactor RY2 are respectively arranged at the positions divided into two, two, two, and one.

  In the above-described embodiment, the example in which the control circuit 20 is installed at a position one step lower than the positive contactor RY1 and the negative contactor RY2 has been described. However, by installing a submergence sensor at the position, the positive contactor RY1 is provided. And you may install in the same height as the negative electrode side contactor RY2. When the submergence sensor detects submergence, it outputs a detection signal to the control circuit 20, and when receiving the detection signal, the control circuit 20 opens the positive contactor RY1 and the negative contactor RY2.

  Moreover, although the example which uses the power supply system 1 for a vehicle power supply device was assumed in the above-mentioned embodiment, it is not limited to a vehicle-mounted application, but for other uses such as an aircraft power supply device, a ship power supply device, a stationary power storage system, etc. Is also available.

  The embodiment may be specified by the following items.

[Item 1]
A plurality of power storage modules (11-14) connected in series;
A fuse (F1) inserted at a position dividing the plurality of power storage modules (11-14) into a first group and a second group on a path connecting the plurality of power storage modules (11-14) in series; ,
A positive contactor (RY1) inserted at a position where the plurality of power storage modules (11, 12) belonging to the first group are divided into a first subgroup and a second subgroup;
A negative contactor (RY2) inserted at a position where the plurality of power storage modules (13, 14) belonging to the second group are divided into a first subgroup and a second subgroup;
A power supply system (1) comprising:
According to this, when a cell is short-circuited due to water immersion, the voltage applied between the cells can be reduced.
[Item 2]
The positive electrode side contactor (RY1), the fuse (F1), and the negative electrode side contactor (RY2) are respectively inserted at positions where the plurality of power storage modules (11-14) are divided into approximately four equal parts. The power supply system (1) according to item 1.
According to this, when the cell is short-circuited due to water immersion, the maximum voltage applied between the cells can be reduced to approximately 1/4.
[Item 3]
A connector (30) for connecting both ends of the plurality of power storage modules (11-14) and an external load (3);
3. The power supply system (1) according to item 1 or 2, wherein the connector (30) is installed at a position lower than the fuse (F1) in a prescribed installation state of the power supply system (1).
According to this, when the connector (30) is submerged, it can be ensured that the fuse (F1) is normally blown out.
[Item 4]
A control circuit (20) for controlling the positive contactor (RY1) and the negative contactor (RY2);
In the specified installation state of the power supply system (1), the connector (30) is installed on the lowermost side, the control circuit (20) is installed on the lower side, the fuse (F1), and the positive electrode side. The power supply system (1) according to item 3, wherein the contactor (RY1) and the negative electrode side contactor (RY2) are installed on the uppermost side.
According to this, a time difference can be generated between the fusing timing of the fuse (F1) and the opening timing of the positive contactor (RY1) and the negative contactor (RY2).
[Item 5]
Each of the plurality of power storage modules (11-14) is installed in a direction in which electrodes are arranged on the upper surface in a prescribed installation state of the power supply system (1),
The fuse (F1), the positive electrode side contactor (RY1), and the negative electrode side contactor (RY2) are installed at substantially horizontal positions with the electrodes of the plurality of power storage modules (11-14). Item 5. The power supply system (1) according to item 4.
According to this, it is possible to delay the flooding of the electrodes, the fuse (F1), the positive contactor (RY1) and the negative contactor (RY2) of the power storage module (11-14), and the fuse (F1), the positive contactor ( The shut-off mechanism by RY1) and the negative electrode side contactor (RY2) can be kept normal as long as possible after flooding.

  DESCRIPTION OF SYMBOLS 1 Power supply system, 2 Inverter, 3 Motor, 11 1st electrical storage module, 12 2nd electrical storage module, 13 3rd electrical storage module, 14 4th electrical storage module, RY1 Positive side contactor, RY2 Negative side contactor, RY3 Precharge contactor, R1 Precharge resistor, CT1 current sensor, F1 fuse, 20 control circuit, 30 connector.

Claims (5)

A plurality of power storage modules connected in series;
On the path connecting the plurality of power storage modules in series, a fuse inserted at a position dividing the plurality of power storage modules into a first group and a second group;
A positive contactor inserted into a position where the plurality of power storage modules belonging to the first group are divided into a first subgroup and a second subgroup;
A negative contactor inserted into a position where the plurality of power storage modules belonging to the second group are divided into a first subgroup and a second subgroup;
A power supply system comprising:   2. The power supply system according to claim 1, wherein the positive electrode side contactor, the fuse, and the negative electrode side contactor are respectively inserted into positions where the plurality of power storage modules are divided into approximately four equal parts. Further comprising both ends of the plurality of power storage modules, and a connector for connecting an external load,
The power supply system according to claim 1, wherein the connector is installed at a position lower than the fuse in a prescribed installation state of the power supply system. A control circuit for controlling the positive contactor and the negative contactor;
In the specified installation state of the power supply system, the connector is installed on the lowermost side, the control circuit is installed on the lower side, and the fuse, the positive contactor and the negative contactor are installed on the uppermost side. The power supply system according to claim 3. Each of the plurality of power storage modules is installed in a direction in which electrodes are arranged on the upper surface in a prescribed installation state of the power supply system,
5. The power supply system according to claim 4, wherein the fuse, the positive electrode side contactor, and the negative electrode side contactor are installed at substantially horizontal positions with respect to the electrodes of the plurality of power storage modules.

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